Transport properties of vanadium germanate glassy semiconductors.

摘要: Measurements are reported for the dc as well frequency-dependent (ac) conductivities (real and imaginary parts) various compositions of vanadium germanate glassy semiconductors in temperature range 80--450 K. The experimental results analyzed with reference to theoretical models proposed electrical conduction amorphous semiconductors. analysis shows that at high temperatures dependence conductivity is consistent Mott's model phonon-assisted polaronic hopping adiabatic approximation, while variable-range-hopping mechanism dominates lower temperatures. Schnakenberg's predicts observed activation energy intermediate range. ac simple quantum-mechanical tunneling temperatures, although this cannot predict frequency exponent. overlapping-large-polaron can explain exponent low temperature; however, a much higher than data show. On other hand, correlated-barrier-hopping both its over entire measurements.